1904. J FHOM EAST AFRICA AXD ZAXZIBAR, 387 



next to the rhachis bear 3-4 small denticles on each side, and 

 those nearest to them are somewhat similar but denticulate only 

 on the outer side ; the others are long and hamate, with about 

 8 denticles on the outer side (PI. XXIII. fig. 4, a, h, c). The 

 outermost bear 3-4 denticles on the apex. A drawing of the 

 alimentary canal is annexed (PI. XXIII. fig. 5). 



I think these animals can be referred to Chr. reticulata Pease, 

 with which Collingwood's Chr. alderi seems to be identical. All 

 my specimens are flat, with ample mantle-margins, an<l this 

 agrees with Collingwood's description and plate. Bergh, on the 

 contrary, says : " Die Korperform ist langlich nicht sehr nieder- 

 gedruckt . . . der Mantelsaum ziemlich schmal." But these soft 

 Chromodoi'ids have great powers of changing their shape and 

 proportions. The branchife are much more numerous than in the 

 specimens previously described, but a multiplication of the small 

 plumes in the spiral does not appear to constitute a specific 

 difference. 



2. ClIROMODORIS SYKESI. (Plate XXIII. fig. 6.) 



Chromodoris sykesi Eliot, Abstr. P. Z. S. 1904, Xo. 4, p. 15, 

 March 8. 



Numerous specimens from the East Coast of Zanzibar, obtained 

 both on the shore and by di-edging. A few of the animals were 

 of a reddish brown with dii'ty yellow markings, but in the 

 majority the coloration was most gorgeous (PI. XXIII. fig. 6). 

 The dorsal surface was bright orange, passing into light yellow 

 towards the edge of the mantle, round which was a double border 

 of reddish brown internally and bi'ight violet externally. On the 

 back were numerous rings of opaque white, but otherwise the 

 whole body w^as translucent. The foot and underside of mantle 

 were of a rich light yellow. The rhinophores and branchife were 

 both of a deep brown-red with opnque white spots. The per- 

 foliations of the rhinophores were indistinct, and the pinnfe of 

 the branchia; small though made conspicuous by white lines 

 drawn along them. The animal was rather flat and very soft. 

 The mantle was very ample. 



The lai'gest alcoholic specimen is 40 mm. long, 27 broad, and 

 10 high. The free edge of the mantle measures 7 mm. over the 

 head, 10 at the sides of the body, nnd 13 over the tail. In giving 

 the measurements, the breadth of the body is estimated as the 

 mantle falls in its normal position: the edge of the mantle is 

 taken as extended, but not stretched unnaturally. The openings 

 of the rhinophores and biunchia^ are small and only slightly raised, 

 but the inteinor of the branchial pocket is a capacious and very 

 strong bag. The branchife are arranged as in Chr. retimdata and 

 vary from 12 to 18, accoi'ding to the size of the spiral. They are 

 red and striped with white. The anal papilla is tall, red and 

 spotted with white. The foot is rounded and grooved in front. 

 Two rather strong folds connect the upper lamina with the 

 corners of the mouth. The oral tentacles were not distinctly 



Proc. Zool. Soc— 1904, Yol. T. Xo. XXVI. 26 



[9] 



